Rapid detection of aluminum residue in pasta

1.
Background introduction

Aluminum is not an essential element for the human body.
So far, it has not been found that when the human body lacks aluminum, it will bring any damage to the health.
On the contrary, excessive intake of aluminum salt can cause the human body to be poisoned
.

Studies have shown that the commonly used leavening agents ( potassium aluminum sulfate dodecahydrate ) in pasta foods such as steamed buns and fried dough sticks can significantly increase the aluminum content in foods.

Recently, the General Administration of Market Supervision has approved and issued 4 rapid food testing methods.
The "Colorimetric Method for Rapid Detection of Aluminum Residues in Flour Products" is one of them.
This standard method is suitable for deep-fried dough sticks, oil cakes, twists, and seeds.
Rapid detection of aluminum residues in pasta products
.

In addition, GB2760-2014 "Food Safety National Standards for the Use of Food Additives" has regulations on the residues of potassium aluminum sulfate (potassium alum) and ammonium aluminum sulfate (ammonium alum), which stipulate the residual amount of aluminum in fried noodles The amount is less than or equal to 100mg/kg (dry sample, calculated as aluminum)

2.
Experimental principle and preparation

Principle: After the aluminum in the sample is extracted with nitric acid solution, in the presence of ethylenediamine -hydrochloric acid buffer, polyethylene glycol octylphenyl ether and cetyltrimethylammonium bromide , aluminum ions and chrome azurite S reacts to produce a blue complex, the color of which is positively correlated with the aluminum content
.

The aluminum content in the sample can be quickly detected by visual color comparison with the standard tube .

Sample preparation: Weigh 1.
0g sample of small twist and spice, weigh 1.
5g sample of fried dough sticks, oil cakes and other fried noodle products, accurate to 0.
01g, and place them in a 50mL centrifuge tube
.

Add about 40mL water and 2mL nitric acid solution successively, make the volume up to 50mL with water, screw the cap of the tube tightly and mix evenly, take it out and mix it in a water bath above 95℃ for 20min, and wait for measurement

Three, content determination

1.

2.

Reagents in supporting standards

Four, method comparison

Comparison of aluminum content test methods

 

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